package com.jtw.common.util;

import org.apache.commons.lang3.RandomStringUtils;

import java.io.UnsupportedEncodingException;
import java.math.BigDecimal;
import java.util.HashSet;
import java.util.Random;
import java.util.Set;

/**
 * 随机数
 */
public class RandomUtil {
//	public static final char [] BASE = new char[]{'0','1','2','3','4','5','6','7','8','9'};
	/**
	 * 自定义进制(0,1没有加入,容易与o,l混淆)，数组顺序可进行调整增加反推难度，A用来补位因此此数组不包含A，共31个字符。
	 */
	private static final char[] BASE = new char[]{'H', 'V', 'E', '8', 'S', '2', 'D', 'Z', 'X', '9', 'C', '7', 'P',
			'5', 'I', 'K', '3', 'M', 'J', 'U', 'F', 'R', '4', 'W', 'Y', 'L', 'T', 'N', '6', 'B', 'G', 'Q'};

	/**
	 * A补位字符，不能与自定义重复
	 */
	private static final char SUFFIX_CHAR = 'A';

	/**
	 * 进制长度
	 */
	private static final int BIN_LEN = BASE.length;

	/**
	 * 生成邀请码最小长度
	 */
	private static final int CODE_LEN = 4;

	/**
	 * 获取数字随机数
	 * @param i
	 * @return
	 */
	public static String getNumber(int i) {
		StringBuffer sb = new StringBuffer();
		for(int j=0; j<i; j++) {
			sb.append(new Random().nextInt(10));
		}
		return sb.toString();
	}

	public static String getRandomValueForNumber(int count){
		return RandomStringUtils.random(count,BASE);
	}

	/**
	 * 根据用户id计算邀请码
	 * @param id
	 * @return
	 */
	public static String idToCode(Long id) {
		char[] buf = new char[BIN_LEN];
		int charPos = BIN_LEN;

		// 当id除以数组长度结果大于0，则进行取模操作，并以取模的值作为数组的坐标获得对应的字符
		while (id / BIN_LEN > 0) {
			int index = (int) (id % BIN_LEN);
			buf[--charPos] = BASE[index];
			id /= BIN_LEN;
		}

		buf[--charPos] = BASE[(int) (id % BIN_LEN)];
		// 将字符数组转化为字符串
		String result = new String(buf, charPos, BIN_LEN - charPos);

		// 长度不足指定长度则随机补全
		int len = result.length();
		if (len < CODE_LEN) {
			StringBuilder sb = new StringBuilder();
			sb.append(SUFFIX_CHAR);
			Random random = new Random();
			// 去除SUFFIX_CHAR本身占位之后需要补齐的位数
			for (int i = 0; i < CODE_LEN - len - 1; i++) {
				sb.append(BASE[random.nextInt(BIN_LEN)]);
			}

			result += sb.toString();
		}

		return result;
	}

	/**
	 * 邀请码解析出ID<br/>
	 * 基本操作思路恰好与idToCode反向操作。
	 *
	 * @param code
	 * @return
	 */
	public static Long codeToId(String code) {
		char[] charArray = code.toCharArray();
		long result = 0L;
		for (int i = 0; i < charArray.length; i++) {
			int index = 0;
			for (int j = 0; j < BIN_LEN; j++) {
				if (charArray[i] == BASE[j]) {
					index = j;
					break;
				}
			}

			if (charArray[i] == SUFFIX_CHAR) {
				break;
			}

			if (i > 0) {
				result = result * BIN_LEN + index;
			} else {
				result = index;
			}
		}

		return result;

	}

	public static String getChineseName() {
		String str = null;
		String name = null;
		int highPos, lowPos;
		Random random = new Random();
		//区码，0xA0打头，从第16区开始，即0xB0=11*16=176,16~55一级汉字，56~87二级汉字
		highPos = (176 + Math.abs(random.nextInt(72)));
		random=new Random();
		//位码，0xA0打头，范围第1~94列
		lowPos = 161 + Math.abs(random.nextInt(94));

		byte[] bArr = new byte[2];
		bArr[0] = (new Integer(highPos)).byteValue();
		bArr[1] = (new Integer(lowPos)).byteValue();
		try {
			//区位码组合成汉字
			str = new String(bArr, "UTF-8");
			int index=random.nextInt(Surname.length-1);
			//获得一个随机的姓氏
			name = Surname[index] +str;

		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
		return name;
	}

	//百家姓
	private static final String[] Surname= {"赵","钱","孙","李","周","吴","郑","王","冯","陈","褚","卫","蒋","沈","韩","杨","朱","秦","尤","许",
			"何","吕","施","张","孔","曹","严","华","金","魏","陶","姜","戚","谢","邹","喻","柏","水","窦","章","云","苏","潘","葛","奚","范","彭","郎",
			"鲁","韦","昌","马","苗","凤","花","方","俞","任","袁","柳","酆","鲍","史","唐","费","廉","岑","薛","雷","贺","倪","汤","滕","殷",
			"罗","毕","郝","邬","安","常","乐","于","时","傅","皮","卞","齐","康","伍","余","元","卜","顾","孟","平","黄","和",
			"穆","萧","尹","姚","邵","湛","汪","祁","毛","禹","狄","米","贝","明","臧","计","伏","成","戴","谈","宋","茅","庞","熊","纪","舒",
			"屈","项","祝","董","梁","杜","阮","蓝","闵","席","季","麻","强","贾","路","娄","危","江","童","颜","郭","梅","盛","林","刁","钟",
			"徐","邱","骆","高","夏","蔡","田","樊","胡","凌","霍","虞","万","支","柯","昝","管","卢","莫","经","房","裘","缪","干","解","应",
			"宗","丁","宣","贲","邓","郁","单","杭","洪","包","诸","左","石","崔","吉","钮","龚","程","嵇","邢","滑","裴","陆","荣","翁","荀",
			"羊","于","惠","甄","曲","家","封","芮","羿","储","靳","汲","邴","糜","松","井","段","富","巫","乌","焦","巴","弓","牧","隗","山",
			"谷","车","侯","宓","蓬","全","郗","班","仰","秋","仲","伊","宫","宁","仇","栾","暴","甘","钭","厉","戎","祖","武","符","刘","景",
			"詹","束","龙","叶","幸","司","韶","郜","黎","蓟","溥","印","宿","白","怀","蒲","邰","从","鄂","索","咸","籍","赖","卓","蔺","屠",
			"蒙","池","乔","阴","郁","胥","能","苍","双","闻","莘","党","翟","谭","贡","劳","逄","姬","申","扶","堵","冉","宰","郦","雍","却",
			"璩","桑","桂","濮","牛","寿","通","边","扈","燕","冀","浦","尚","农","温","别","庄","晏","柴","瞿","阎","充","慕","连","茹","习",
			"宦","艾","鱼","容","向","古","易","慎","戈","廖","庾","终","暨","居","衡","步","都","耿","满","弘","匡","国","文","寇","广","禄",
			"阙","东","欧","殳","沃","利","蔚","越","夔","隆","师","巩","厍","聂","晁","勾","敖","融","冷","訾","辛","阚","那","简","饶","空",
			"曾","毋","沙","乜","养","鞠","须","丰","巢","关","蒯","相","查","后","荆","红","游","郏","竺","权","逯","盖","益","桓","公","仉",
			"督","岳","帅","缑","亢","况","郈","有","琴","归","海","晋","楚","闫","法","汝","鄢","涂","钦","商","牟","佘","佴","伯","赏","墨",
			"哈","谯","篁","年","爱","阳","佟","言","福","南","火","铁","迟","漆","官","冼","真","展","繁","檀","祭","密","敬","揭","舜","楼",
			"疏","冒","浑","挚","胶","随","高","皋","原","种","练","弥","仓","眭","蹇","覃","阿","门","恽","来","綦","召","仪","风","介","巨",
			"木","京","狐","郇","虎","枚","抗","达","杞","苌","折","麦","庆","过","竹","端","鲜","皇","亓","老","是","秘","畅","邝","还","宾",
			"闾","辜","纵","侴","万俟","司马","上官","欧阳","夏侯","诸葛","闻人","东方","赫连","皇甫","羊舌","尉迟","公羊","澹台","公冶","宗正",
			"濮阳","淳于","单于","太叔","申屠","公孙","仲孙","轩辕","令狐","钟离","宇文","长孙","慕容","鲜于","闾丘","司徒","司空","兀官","司寇",
			"南门","呼延","子车","颛孙","端木","巫马","公西","漆雕","车正","壤驷","公良","拓跋","夹谷","宰父","谷梁","段干","百里","东郭","微生",
			"梁丘","左丘","东门","西门","南宫","第五","公仪","公乘","太史","仲长","叔孙","屈突","尔朱","东乡","相里","胡母","司城","张廖","雍门",
			"毋丘","贺兰","綦毋","屋庐","独孤","南郭","北宫","王孙"};

	public static void main(String[] args) {
//		System.out.println(new BigDecimal(Math.pow(32,7)).toPlainString());
//		System.out.println(getNumber(6));
//		Set<String> set = new HashSet<>();
//		for(int i = 1;i<=1000000;i++){
//			set.add(idToCode(Long.valueOf(i+"")));
//		}
//		System.out.println(set.size());
		System.out.println(getChineseName());
	}
}
